Still it is never a good idea to install Software this way if there is another software package that may overwrite components needed for the other. Carefully saying: System Engineers/Consultants recommending using Software this way are either missing the experience or don’t really care about the reliability of such systems.
With Docker this is another story of course. But as said there is a reliable image missing, yet.
Point well taken. The setup is not for advanced users / larger installations whose infrastructure/network is in a constant state of flux.
As the tutorial says (paraphrased): “This setup is recommended for small teams / small enterprises that want to use Seafile while not forfeiting the easy server administration (e-mails, subdomains, SSL) that comes with Plesk.”